include/asm-arm/memory.h

   1 /*
   2  *  linux/include/asm-arm/memory.h
   3  *
   4  *  Copyright (C) 2000-2002 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  *  Note: this file should not be included by non-asm/.h files
  11  */
  12 #ifndef __ASM_ARM_MEMORY_H
  13 #define __ASM_ARM_MEMORY_H
  14
  15 /*
  16  * Allow for constants defined here to be used from assembly code
  17  * by prepending the UL suffix only with actual C code compilation.
  18  */
  19 #ifndef __ASSEMBLY__
  20 #define UL(x) (x##UL)
  21 #else
  22 #define UL(x) (x)
  23 #endif
  24
  25 #include <linux/compiler.h>
  26 #include <asm/arch/memory.h>
  27 #include <asm/sizes.h>
  28
  29 #ifndef TASK_SIZE
  30 /*
  31  * TASK_SIZE - the maximum size of a user space task.
  32  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
  33  */
  34 #define TASK_SIZE               UL(0xbf000000)
  35 #define TASK_UNMAPPED_BASE      UL(0x40000000)
  36 #endif
  37
  38 /*
  39  * The maximum size of a 26-bit user space task.
  40  */
  41 #define TASK_SIZE_26            UL(0x04000000)
  42
  43 /*
  44  * Page offset: 3GB
  45  */
  46 #ifndef PAGE_OFFSET
  47 #define PAGE_OFFSET             UL(0xc0000000)
  48 #endif
  49
  50 /*
  51  * Size of DMA-consistent memory region.  Must be multiple of 2M,
  52  * between 2MB and 14MB inclusive.
  53  */
  54 #ifndef CONSISTENT_DMA_SIZE
  55 #define CONSISTENT_DMA_SIZE SZ_2M
  56 #endif
  57
  58 /*
  59  * Physical vs virtual RAM address space conversion.  These are
  60  * private definitions which should NOT be used outside memory.h
  61  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
  62  */
  63 #ifndef __virt_to_phys
  64 #define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
  65 #define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
  66 #endif
  67
  68 /*
  69  * Convert a physical address to a Page Frame Number and back
  70  */
  71 #define __phys_to_pfn(paddr)    ((paddr) >> PAGE_SHIFT)
  72 #define __pfn_to_phys(pfn)      ((pfn) << PAGE_SHIFT)
  73
  74 /*
  75  * The module space lives between the addresses given by TASK_SIZE
  76  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  77  */
  78 #define MODULE_END      (PAGE_OFFSET)
  79 #define MODULE_START    (MODULE_END - 16*1048576)
  80
  81 #if TASK_SIZE > MODULE_START
  82 #error Top of user space clashes with start of module space
  83 #endif
  84
  85 /*
  86  * The XIP kernel gets mapped at the bottom of the module vm area.
  87  * Since we use sections to map it, this macro replaces the physical address
  88  * with its virtual address while keeping offset from the base section.
  89  */
  90 #define XIP_VIRT_ADDR(physaddr)  (MODULE_START + ((physaddr) & 0x000fffff))
  91
  92 #ifndef __ASSEMBLY__
  93
  94 /*
  95  * The DMA mask corresponding to the maximum bus address allocatable
  96  * using GFP_DMA.  The default here places no restriction on DMA
  97  * allocations.  This must be the smallest DMA mask in the system,
  98  * so a successful GFP_DMA allocation will always satisfy this.
  99  */
 100 #ifndef ISA_DMA_THRESHOLD
 101 #define ISA_DMA_THRESHOLD       (0xffffffffULL)
 102 #endif
 103
 104 #ifndef arch_adjust_zones
 105 #define arch_adjust_zones(node,size,holes) do { } while (0)
 106 #endif
 107
 108 /*
 109  * PFNs are used to describe any physical page; this means
 110  * PFN 0 == physical address 0.
 111  *
 112  * This is the PFN of the first RAM page in the kernel
 113  * direct-mapped view.  We assume this is the first page
 114  * of RAM in the mem_map as well.
 115  */
 116 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 117
 118 /*
 119  * These are *only* valid on the kernel direct mapped RAM memory.
 120  * Note: Drivers should NOT use these.  They are the wrong
 121  * translation for translating DMA addresses.  Use the driver
 122  * DMA support - see dma-mapping.h.
 123  */
 124 static inline unsigned long virt_to_phys(void *x)
 125 {
 126         return __virt_to_phys((unsigned long)(x));
 127 }
 128
 129 static inline void *phys_to_virt(unsigned long x)
 130 {
 131         return (void *)(__phys_to_virt((unsigned long)(x)));
 132 }
 133
 134 /*
 135  * Drivers should NOT use these either.
 136  */
 137 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 138 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 139 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 140
 141 /*
 142  * Virtual <-> DMA view memory address translations
 143  * Again, these are *only* valid on the kernel direct mapped RAM
 144  * memory.  Use of these is *deprecated* (and that doesn't mean
 145  * use the __ prefixed forms instead.)  See dma-mapping.h.
 146  */
 147 static inline __deprecated unsigned long virt_to_bus(void *x)
 148 {
 149         return __virt_to_bus((unsigned long)x);
 150 }
 151
 152 static inline __deprecated void *bus_to_virt(unsigned long x)
 153 {
 154         return (void *)__bus_to_virt(x);
 155 }
 156
 157 /*
 158  * Conversion between a struct page and a physical address.
 159  *
 160  * Note: when converting an unknown physical address to a
 161  * struct page, the resulting pointer must be validated
 162  * using VALID_PAGE().  It must return an invalid struct page
 163  * for any physical address not corresponding to a system
 164  * RAM address.
 165  *
 166  *  page_to_pfn(page)   convert a struct page * to a PFN number
 167  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 168  *  pfn_valid(pfn)      indicates whether a PFN number is valid
 169  *
 170  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 171  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 172  */
 173 #ifndef CONFIG_DISCONTIGMEM
 174 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 175 #define pfn_valid(pfn)          ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
 176
 177 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 178 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 179
 180 #define PHYS_TO_NID(addr)       (0)
 181
 182 #else /* CONFIG_DISCONTIGMEM */
 183
 184 /*
 185  * This is more complex.  We have a set of mem_map arrays spread
 186  * around in memory.
 187  */
 188 #include <linux/numa.h>
 189 #define arch_pfn_to_nid(pfn)    PFN_TO_NID(pfn)
 190 #define arch_local_page_offset(pfn, nid) LOCAL_MAP_NR((pfn) << PAGE_SHIFT)
 191
 192 #define pfn_valid(pfn)                                          \
 193         ({                                                      \
 194                 unsigned int nid = PFN_TO_NID(pfn);             \
 195                 int valid = nid < MAX_NUMNODES;                 \
 196                 if (valid) {                                    \
 197                         pg_data_t *node = NODE_DATA(nid);       \
 198                         valid = (pfn - node->node_start_pfn) <  \
 199                                 node->node_spanned_pages;       \
 200                 }                                               \
 201                 valid;                                          \
 202         })
 203
 204 #define virt_to_page(kaddr)                                     \
 205         (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
 206
 207 #define virt_addr_valid(kaddr)  (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
 208
 209 /*
 210  * Common discontigmem stuff.
 211  *  PHYS_TO_NID is used by the ARM kernel/setup.c
 212  */
 213 #define PHYS_TO_NID(addr)       PFN_TO_NID((addr) >> PAGE_SHIFT)
 214
 215 #endif /* !CONFIG_DISCONTIGMEM */
 216
 217 /*
 218  * For BIO.  "will die".  Kill me when bio_to_phys() and bvec_to_phys() die.
 219  */
 220 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 221
 222 /*
 223  * Optional device DMA address remapping. Do _not_ use directly!
 224  * We should really eliminate virt_to_bus() here - it's deprecated.
 225  */
 226 #ifndef __arch_page_to_dma
 227 #define page_to_dma(dev, page)          ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
 228 #define dma_to_virt(dev, addr)          ((void *)__bus_to_virt(addr))
 229 #define virt_to_dma(dev, addr)          ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
 230 #else
 231 #define page_to_dma(dev, page)          (__arch_page_to_dma(dev, page))
 232 #define dma_to_virt(dev, addr)          (__arch_dma_to_virt(dev, addr))
 233 #define virt_to_dma(dev, addr)          (__arch_virt_to_dma(dev, addr))
 234 #endif
 235
 236 /*
 237  * Optional coherency support.  Currently used only by selected
 238  * Intel XSC3-based systems.
 239  */
 240 #ifndef arch_is_coherent
 241 #define arch_is_coherent()              0
 242 #endif
 243
 244 #endif
 245
 246 #include <asm-generic/memory_model.h>
 247
 248 #endif